S
M
T
W
T
F
S
30
90°
80°
31
90°
79°
1
89°
80°
2
90°
80°
3
90°
79°
4
89°
79°
5
89°
80°
6
90°
80°
7
90°
79°
8
89°
80°
9
88°
78°
10
89°
80°
11
88°
79°
12
89°
78°
13
88°
80°
14
89°
79°
15
89°
79°
16
88°
80°
17
88°
79°
18
89°
80°
19
89°
80°
20
88°
81°
21
89°
80°
22
88°
80°
23
89°
79°
24
88°
80°
25
89°
81°
26
90°
80°
27
90°
80°
28
89°
79°
29
89°
79°
30
89°
80°
1
Hist. Avg.
89°
79°
2
Hist. Avg.
89°
79°
3
Hist. Avg.
89°
79°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
September Weather in St Thomas
St Thomas's September 2026 forecast shows daily high temperatures ranging from 88° to 90°, with overnight lows between 78° and 81°. The average high for September is 89° with an average low of 80°. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how September weather will actually feel in St Thomas. See also: October | November | December.
